Heat pipe manufacturing method and heat pipe thereof

ABSTRACT

A heat pipe includes a step pipe, a mesh, and a supporting component. The step pipe has an evaporating section and two condensing sections. The condensing sections are on the two ends of the step pipe, respectively. The evaporating section lies between the two condensing sections. The inner spaces of the two condensing sections and the evaporating section are interconnected. The peripheral dimension of the evaporating section is larger than the peripheral dimension of each of the condensing sections. The mesh is contained in the step pipe and located inside the evaporating section. The supporting component is contained in the step pipe and wrapped in the mesh. The combination of these structures increases air&#39;s flow rate inside the heat pipe and improves the heat pipe&#39;s heat conduction efficiency.

BACKGROUND

1. Technical Field

The present invention generally relates to a heat pipe, and more particularly, to a method of manufacturing a heat pipe and a heat pipe thereof.

2. Related Art

The exacerbating problems caused by electronic heat sources can be resolved by using heat pipes to dissipate heat in electronic products. Replacing cooling structures formed by cooling fins with heat pipes is apparently the future development trend. In addition to fit in with the premises that electronic products need to be light, thin, short, and small, it's also desirable to further enhance a heat pipe's heat-conduction efficiency.

A conventional heat pipe generally includes a round pipe with a fixed diameter, a capillary structure, and a working fluid. The round pipe has a containing chamber in its interior. The capillary structure is set inside the containing chamber and stuck to the inner surface of the pipe. The working fluid is filled in the containing chamber and accumulated in the capillary structure. As a whole, these parts form a conventional heat pipe.

However, because the diameter of the round pipe is fixed, the inner working fluid could not speed up the heat dissipation rate when it evaporates. Therefore, the heat pipe's heat conduction efficiency is relatively limited. Furthermore, because the capillary structure is a homogeneous structure, its flow-back rate is relatively low and hence might not prevent the heat pipe from drying out. In addition, because the heat pipe's evaporation section has a small sectional area, the heat pipe cannot provide a large area to contact with the heat source. Therefore, the heat pipe can only generate a small amount of steam, and the amount is insufficient to prevent heat accumulation. As a result, it's difficult to effectively improve the conventional heat pipe's heat dissipation efficiency.

BRIEF SUMMARY

Embodiments of the present invention provide a method of manufacturing a heat pipe and a heat pipe thereof. Because in each of the embodiments the peripheral dimension of an evaporating section is different from the peripheral dimensions of a plurality of condensing sections, the embodiments can increase air's flow rate inside the heat pipe and improve the heat pipe's heat conduction efficiency.

An embodiment of the present invention provides a method of manufacturing a heat pipe. The method includes the following steps: a) providing a hollow pipe, a mesh, and a supporting component, wrapping the supporting component with the mesh and then inserting the supporting component and the mesh into the hollow pipe; b) inserting an insertion rod into the step pipe and letting the insertion rod contact the supporting component; and c) after step b) shrinking a part of the hollow pipe and the insertion rod so as to convert the hollow pipe into a step pipe having varying peripheral dimensions.

Another embodiment of the present invention provides a heat pipe. The heat pipe includes a step pipe, a mesh, and a supporting component. The step pipe has an evaporating section and two condensing sections. The two condensing sections are on two ends of the step pipe, respectively. The evaporating section lies between the two condensing sections. The inner spaces of the two condensing sections and the evaporating section are interconnected. The peripheral dimension of the evaporating section is larger than the peripheral dimension of each of the condensing sections. The mesh is contained in the step pipe and located inside the evaporating section. The supporting component is contained in the step pipe and wrapped in the mesh.

The embodiments have the following advantages. The composite capillary structure in each of the condensing sections improves the liquid flow-back rate and hence prevents dry out. The relatively larger sectional area of the evaporating section increases the contact area between the evaporating section and a heat source, allows more steam to be generated, and hence improves the heat dissipation efficiency. Because the sectional area of the evaporating section is larger than the sectional areas of the condensing sections and because sectional area is inversely proportional to flow rate, when the working fluid receives enough heat and evaporates, the resulting air will have a higher flow rate.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a flowchart of a heat pipe manufacturing method according to an embodiment of the present invention;

FIG. 2 shows an exploded diagram of a heat pipe according to an embodiment of the present invention;

FIG. 3 and shows a sectional view of the heat pipe;

FIG. 4 and FIG. 5 show sectional views of a step pipe inserted with an insertion rod according to an embodiment of the present invention;

FIG. 6 shows a perspective view of the heat pipe;

FIG. 7 shows a sectional view of the heat pipe;

FIG. 8 shows a perspective view of the heat pipe after being flattened;

FIG. 9 shows a sectional view of the heat pipe after being flattened; and

FIG. 10 shows a sectional view of an evaporating section of a heat pipe according to another embodiment of the present invention.

DETAILED DESCRIPTION

Please refer to FIG. 1 to FIG. 5. An embodiment of the present invention provides a method of manufacturing a heat pipe. The method includes the following steps.

a) Provide a hollow pipe 10, a mesh 20, and a supporting component 30, cover the supporting component 30 with the mesh 20, and place the two into the hollow pipe 10. Please refer to FIG. 2 and FIG. 3. In this embodiment, the hollow pipe 10 is composed of, but is not limited to, material with good heat-conductivity and ductility, such as copper or copper alloy. The hollow pipe 10 in this embodiment is a straight round pipe, having a containing chamber 11 in its interior. The inner wall of the hollow pipe 10 is a smooth surface. The supporting component 30 in this embodiment is a helical spring. The supporting component 30 is first wrapped in the mesh 20; then the two are placed in the hollow pipe 10 together.

b) Insert an insertion rod 6 into the hollow pipe 10 and cause the insertion rod 6 to contact the supporting component 30. Please refer to FIG. 4. This step can include inserting a single insertion rod 6 into the hollow pipe 10 so that the single insertion rod 6 contacts the supporting component 30, and then shrinking the hollow pipe 10 on a single end. As another alternative, this step can include inserting two insertion rods 6 into the hollow pipe 10 from different directions so that the two insertion rods 6 contact the supporting component 30, and then shrinking the hollow pipe 10.

c) Shrink some areas of the hollow pipe 10, which contains the insertion rod 6, so as to convert the hollow pipe 10 into a step pipe 10 a with varying peripheral dimensions. Please refer to FIG. 4, at this step, the hollow pipe 10 that contains the insertion rod 6 and has a fixed peripheral dimension is sent into a shaping mold, which is not shown in the figure. This shaping mold is used to shrink the areas on the two ends of the hollow pipe 10. As a result, the step pipe 10 a has a larger peripheral dimension in the middle area and smaller peripheral dimensions on the two ends.

In addition, the embodiment can further include a step d) after step c). At step d), an insertion rod 7 is inserted into the step pipe 10 a and a metal powder 40 is filled in the space between the insertion rod 7 and the step pipe 10 a. Please refer to FIG. 5, at this step, the insertion rod 7 is first inserted into the step pipe 10 a and then the metal powder 40 is filled in the space between the step pipe 10 a and the insertion rod 7. The metal powder 40 in this embodiment is filled in the shrunk areas on the two ends of the step pipe 10 a.

Moreover, the embodiment can further include a step e) after step d). At step e), the step pipe 10 a and the insertion rod 7 are sintered so that a sintered powder structure 40 a is formed on the inner wall of the step pipe 10 a. At this step, the step pipe 10 a and the insertion rod 7 are sent into a sintering furnace for sintering and then the insertion rod 7 is extracted from the step pipe 10 a. As a result, the metal powder 40 will attach to the areas on the two ends of the step pipe 10 a and become the sintered powder structure 40 a shown in FIG. 7.

In addition, the embodiment can further include a step f) after step e). At step f), the step pipe 10 a is sealed up, filled with a working fluid 30, and degassed. Please refer to FIG. 6 and FIG. 7, at this step, a sealing apparatus, which is not depicted in the figure, is used to solder and seal an end of the step pipe 10 a. Then, the working fluid 30 is filled into the step pipe 10 a through the not yet sealed end of the step pipe 10 a. Next, the step pipe 10 a that is filled with the working fluid 30 is degassed. The other end of the step pipe 10 a is then soldered and sealed. Eventually, the heat pipe 1 of the embodiment is finished, where the heat pipe 1 in this embodiment is a straight step pipe with round traverse sections.

Moreover, the embodiment can further include a step g) after step f). At step g), the step pipe 10 a is flattened. Please refer to FIG. 8, at this step, a tool, which is not depicted in the figure, is used to press the step pipe 10 a. As a result, the straight step pipe 10 a becomes flat.

Please refer to FIG. 8 and FIG. 9. Another embodiment of the present invention provides a heat pipe, including a step pipe 10 a, a mesh 20, and a supporting component 30. The step pipe 10 a has an evaporating section 101 and two condensing sections 102 and 103. The two condensing sections 102 and 103 are on the two ends of the step pipe 10 a, and the evaporating section 101 lies between the two condensing sections 102 and 103. The evaporating section 101 can have a thermal contact with an electronic heat source, which is not depicted in the figure. Each of the condensing sections 102 and 103 can conduct heat to cooling components such as cooling fins and cooling blocks, which are not depicted in the figure. The interior of each of the condensing sections 102 and 103 is connected to the interior of the evaporating section 101. The peripheral dimension of the evaporating section 101 is larger than the peripheral dimensions of the condensing sections 102 and 103. In other words, the cross section of the evaporating section 101 is larger than the cross sections of the condensing sections 102 and 103. The mesh 20 is contained in the step pipe 10 a and located inside the evaporating section 101. The supporting component 30 is contained in the step pipe 10 a and wrapped in the mesh 20. In this embodiment, the supporting component 30 is a helical spring.

In addition to the aforementioned configuration, the followings are some alternative configurations. In a first alternative, the evaporating section 101 is round and the condensing sections 102 and 103 are flat. In a second alternative, the evaporating section 101 is flat and the condensing sections 102 and 103 are round. In a third alternative, the evaporating section 101 is semicircular, as shown in FIG. 10, and the condensing sections 102 and 103 are round. In a fourth alternative, the evaporating section 101 is semicircular, and the condensing sections 102 and 103 are flat.

The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments. 

1. A method of manufacturing a heat pipe, comprising: a) providing a hollow pipe, a mesh, and a supporting component, wrapping the supporting component with the mesh and then inserting the supporting component and the mesh into the hollow pipe; b) inserting an insertion rod into the step pipe and letting the insertion rod contact the supporting component; and c) after step b) shrinking a part of the hollow pipe and the insertion rod so as to convert the hollow pipe into a step pipe having varying peripheral dimensions.
 2. The method of claim 1, further comprising a step d) of filling a metal powder into a space between the insertion rod and the step pipe.
 3. The method of claim 2, further comprising a step e) of sintering the step pipe and the insertion rod so as to form a sintered powder structure on an inner wall of the step pipe after step d).
 4. The method of claim 3, further comprising a step f) of sealing the step pipe, filling in a working fluid, and degassing the step pipe after step e).
 5. The method of claim 4, further comprising a step g) of flatting the step pipe after step f).
 6. A heat pipe, comprising: a step pipe, having a evaporating section and two condensing sections, wherein the two condensing sections are formed on two ends of the step pipe, respectively, the evaporating section lies between the two condensing sections, inner spaces of the two condensing sections and the evaporating section are interconnected, and a peripheral dimension of the evaporating section is larger than a peripheral dimension of each of the condensing sections. a mesh, contained in the step pipe and located inside the evaporating section; and a supporting component, contained in the step pipe and wrapped in the mesh.
 7. The heat pipe of claim 6, wherein the heat pipe is a straight step pipe with round traverse sections.
 8. The heat pipe of claim 6, wherein the heat pipe is a straight step pipe with flat traverse sections.
 9. The heat pipe of claim 6, wherein the evaporating section is round, semicircular, or flat.
 10. The heat pipe of claim 9, wherein the condensing sections are round or flat.
 11. The heat pipe of claim 6, wherein the supporting component is a helical spring.
 12. The heat pipe of claim 6, further comprising a sintered powder structure, the sintered powder structure being formed inside either or both of the condensing sections.
 13. The heat pipe of claim 12, further comprising a working fluid, the working fluid being filled inside the step pipe. 